The front-runner energy company in the effort to unlock oil shale in northwest Colorado has slowed down its research by withdrawing an application for a state mining permit.

Shell spokeswoman Jill Davis said the withdrawal of a permit on one of its three oil-shale research and demonstration leases was done for economic reasons: Costs for building an underground wall of frozen water to contain melted shale have “significantly escalated.”

“We are being more cautious and more prudent,” Davis said. “Because of the nature of research you have challenges. With that in mind, it is taking a little longer to build a freeze wall than we planned.”

Davis stressed that the withdrawal of the mining permit does not lessen Shell’s commitment to continuing research at its Mahogany Research Project between Rangely and Meeker and eventually building demonstration projects on its federal leases.

“There is a very active program up there, and that will continue,” Davis said.

The delaying of the freeze-wall test means a plan to hire 600 new workers and build temporary housing for them will be on hold. The more than 40 Shell workers and 150 contractors working on the Mahogany project will not be affected.

Shell’s slowdown does not mean the Bureau of Land Management will delay plans to issue commercial leases as soon as 2008.

“There is no slowdown from our perspective,” said Celia Boddington, national spokesperson for the BLM.

“The BLM should realize there is no rush for commercial leasing,” said Bob Randall, an attorney with Western Resource Advocates. “There is a message for the BLM here.”

Shell is one of three companies awarded federal leases in Colorado to test new methods of extracting oil from shale rock by heating the rock underground rather than by mining it and cooking it above ground.

Shell’s method involves heating shale over a period of years and encircling it in a wall of frozen water to prevent groundwater contamination.

Shell has been researching heating methods on its property in the Piceance Basin for several years and is now in the process of freezing a test wall. Research on that wall will continue.

Spain came under repeated attack starting Thursday in what authorities called linked terrorist incidents, when a driver swerved a van into crowds in Barcelona’s historic Las Ramblas district, killing more than a dozen people and injuring scores of others. Early Friday, an attempted attack unfolded in a town down the coast

If there’s one superhero character whose rise might be most tied to the events of World War II, it is Captain America, who emerged from the minds of legends Joe Simon and Jack Kirby and sprung forth from an iconic 1941 debut cover on which Cap smacks Hitler right in the kisser.

A customer dining at Washington’s Oceanaire restaurant noticed an unusual line at the bottom of his receipt: “Due to the rising costs of doing business in this location, including costs associated with higher minimum wage rates, a 3% surcharge has been added to your total bill.”